Shock absorber



April 3o, 1929. y ,1 W F MANZEL 1,711,173

SHOCK ABsoRBE'R Filed May 24, 1923 15 i5 33 LIME! 3 a i4 31a/vento@ l 4@2M Witness: V

Patented A pr.` 370, 1929.

UNITED STATES PATENT oFF1cE.

ADOLPH W. F.`1VI ANZEL OF BUFFALO, YORK, ASSIGNOR TO MANZEL BROS. C0.,

OF BUFFALO, NEW YORK, A CORPORATION OF NEW'YOBK.

SHOCK ABSORBER.

Application filed May 24,

passage and which are generally referred to.

as hydraulic7 shock absorbers; certain features of the invention,however, being de signed for use in an'y other type of shock absorberacting to suddenly check a rebound When passing into a'rut or overaprojection in the road.

This invention is acontinuation in part of my application for patentSerial No. 560,292, filed May l2, 1922, and issued as Patent No.1,510,185', September 30, 1924.

Shock absorbers, and especially those containing oil as the checkingmedium, offer sud` den resistance to slight jars, such as an automobileis subjected to in passing over roads constructed of cobble stones, orother roads causing sharply emphasized but short and pithy shocks, whichare objectionable and nerve racking, especially When traveling overroads of this kind for any length of time; such shocks, unless absorbed,being transferred to the spine of a person seated Within a vehicle.

While shock absorbers of the type stated are highly desirable andefiicient for absorbing shocks Caused by comparatively'pronounceddepressions or elevations in a road due to the fact that the force ofthe shocks is suficient to' quickly overcome the initial resistanceoffered thereagainst, slight shocks do not create sufficient forceforthis purpose.

and therefore the sudden resistance offered against the shocks inreality make absorbers of this type undesirable. at times, especiallyfor city use or for country driving Where the roads are constructed ofbrick or other ,material which form or have comparatively smalldepressions or elevations.

It is the primary object of my invention to provide a shock absorberwith a main Huid-resisting shock-absorbing device and a secondaryshock-absorbing device, both enclosed Within the same casing andpreferably co-axial, said secondary shock-absorbing de vice beingadapted tobe brought into action 1923. Serial No. 641,151.

upon the main shock absorbing device or, in other words, upon thefluid-resisting portion of the device, shown in the drawing hereof.

Another object of my invention is to provide a shock absorber of thetype stated, in which t-Wo related absorbingmeans or devices arecontained Within a casing or hous-J inga.nd in which one is broughtinto'action after the other, under a force' overcoming the resistance.of one and immediately applied to the other so that the shocks areabsorbed by a resistance offered by the Itvvo without any perceptiblebreak and so that a smooth resisting force is provided under all ridingconditions.

The invention therefore consists ina shock v absorbing device having tWoabsorbing means or devices confined Within a single casing, one of whichis a fluid-resisting means or device and is brought into actionafter theother when the absorbing qualities of one arc consumed during a portionof a shock.

It further consists in providing a hydraulic shock absorber with initialor what may be termed secondary or'auXiliary shock-absorbing means,which alone is brought into action when the automobile or other-,vehicleis subjected to What I term slight staccato shocks.

It further consists in the novel features of construction and in thecombination and arrangement of devices and parts to be hereinafterdescribed vand more particularly c 3 3, Fig. 2.

In Fig-1 of the drawing I have shovvn the parts of an automobile towhich one of my improved shockA absorbers is applied, and in the mannerillustrated, these parts are at the front of the automobile; it being ofcourse understood that a shock absorber is provided at each side of theautomobile or other vehicle,

and that a pair of shock absorbers may be used at the front or the rear,or both at the front and the rear.

The reference numeral 5 designates the -drawn downwardly, the tendencyof the' spring to recover after passing over the rough portion orportions of the road will throw up the body of the vehicle, therebyunduly straining the springs. Even when the shocks or lexure of thesprings are slight, riding with' in the vehicle is uncomfortable, andwhen deep nuts or pronounced elevations are enlcountered, the occupants'are forcibly raised from their seats and dropped back under completeloss of control. e v

The body and spring, or the axle supporting the spring, may beconsidered as two relatively movable vparts of a vehicle, to one ofwhich the housing or casing of my shock absorber is secured and to theother of which an element extending from said housing or casing andactuating parts therein is connected.

The housing or casing is designated by' the numeral 8 and is dividedintotwo chambers 9, 10, by a wall 11. The chamber 9 is cylindrical andserves as a cylinder while thek ,chamber 10 may be of any desiredformation in cross section. The lower ends of the cylinder 9 and chamberV10 are connected 'by a Huid passage 12. The wall 11 extends upwardlyfrom the wall of said passage and terininates in a plane aV distancebeneath the upper end of the casing. Above the upper end of the wall 11,chamber 10 is in direct communication with the cylinder 9,v the`cylindrical formation of the latter being continued upwardly to the topof the casing. The upper end of the casing is closed by a suitable cover13 bolted or otherwise fastened to the casing, with packing providedbetween the upper end of the casing and the cover to prevent leakage ofoil therebetween. The cover 13 is pro*L vided with a fillinglopening y14closed by a. suitable closure 15, oil being furnished to the casingthrough said filling opening. i

` Within the'cylinder 9, a piston'16 is slidably fitted, said piston, inits preferred form, being solid and having an axial upwardlyopeningboreA 17. This 'piston is provided with a reduced lower end 18 to form adownwardly facing shoulder 19 on said piston. Bearing with oneendagainst said shoulder andsurrounding said reduced portion 18 is anexpansion spring 20, the other or lower end of which bears against thebottom of the casing, and more particularly, against the i bottom ofthe,V cylinder 9.

The piston is fitted into the cylinder 9 and r isl adapted for movementtherein. The bottom of the cylinder is provided with a drain opening 22closed by means of a plug or other closure 23 so that oil within thecasing can be conveniently drained whenever found necessary4ordesirable. z

Within the Huid passage 12, fluid-regulating means 24 is located, saidmeans being more particularly set forth in my (3o-pending application,Serial N o. 560,292, filed May 12, 1922. This fluid-regulating meansServes to allow a comparatively free passage of fluid from the chamberl0 into the cylinder 9 when the piston within said cylinder movesupwardly whileit servesto restrict the flow of the fluid from thecylinder 9 tothe chamber 10 which the piston moves downwardly, and whileIhave illustrated a particular regulating means or device within thepassage for this purpose, itis to be understood that any means, whetherwithin a *passage arranged as shown, or otherwise, accomplishingsubstantially the functions of the means shown, may be substituted, asthe particular features of my invention herein referred to as aninitial, or secondary, or auxiliary shock absorbing means may be used inconnection with any kind of regulation means serving to regulate the Howof iuid from. one chamber to another as required in ashock absorber yofthis type. l p

Oil is delivered into the casing through the filling opening 14 inthe'cover and is preferably maintained at a level above the upper end ofthe piston when in normal position. "However, the construction is ofvsuch a nature that the operation of the device will be thorl oughlyeffective if the level is below that stated.V

Projecting fromthe casing are securing lugs 25 by means of which it maybe fastened to the frame or chassis of the vehicle, suitable f bolts orother fastening means being provided for the purpose. Extendingtransversely lthrough the casing is' a rock shaft 26, which.is'preferably integral with a crank or actuating lever 27 extendingfrom one end of said shaft. That portion of the rock shaft positionedbetween the two side walls of the casing has an actuating arm 28 securedthereto, the outer end ofwhich is provided with a rounded contactportion29, for a purpose to appear hereinafter. A strip ofwebbing orother iexible material 30 is secured with one end to the free end of'said actuating lever I 27 and it.has its other end fastened to the axle7 of the vehicle. N v

The upper end of the axial upwardly opening bore 17 of the pistonisenlarged, as at 31, to form an upwardly-facing shoulder 32,

and said enlarged upper end 31 may be said 1 toserve as an auxiliarycylinder.

33 is what maybe termed an auxiliary piston, which is in the formof adisk having an axial air and oil opening 34 therein. This auxiliary.piston is reciprocally held in said axial bore by means to behereinafter described. Within the bore 17 is an expansion spring 35,which lextends vupwardly into the auxiliary cylinder 31 and which may bereferred to as an auxiliary expansion spring.'

Theupper'end of said auxiliary expansion spring, bears against the underside of the disk or auxiliary piston 33, and the lower end thereof bearsagainst the lower wall of the bore 17 within the piston 16, which lattermay be referred to as themain piston, while the cylinder 9 receivingsaid main piston, may be termed the main cylinder.

rlhe upper end of the main piston 16 is reduced in diameter to form anupstanding annular flange or neck 3,6, which surrounds i the auxiliarycylinder or enlarged upper end of the axial bore 17 and at the junctureof said flange or neckto the body portion of said main piston` is anannular groove 37. A stop ring 38 is fitted around the annular flange orneck 36, the lower marginal portion thereof being spun, rolled, or`otherwise forced into the annular groove 37 to prevent upward movementof said ring under pressure, and the upper marginal portion of said'ring being forced inward over the upper edge of the flange or neck soas .to overhang'the inner peripheral surface of said flange or neck, andthus form an annular stop against which the disk or auxiliary piston33.is-n0rmally y held by the action of the auxiliary expansion spring35. The rounded contact portion 29 of the actuating arm is normally inContact. with the upper face ofthe auxiliary piston 33 and the forceexerted by the sprmg 20- for convenience termed the main spring--andfarm, the force of said springs bein the axial. spring 35 v causes .thewebbing or other flexible connection 30 tobe held taut at alll times.=By reason of said springs forcing the auxiliary piston against theactuatig su cient to move said arm upwardly, and y reason of the rockshaft 26 being rotated during the upward movement of said arm,` theouter endk of the actuating lever to which the web# biug or flexiblematerial 30 is secured is forced upwardly.

In Fig. 2, the parts are shown in normal position, and in this positiona comparatively small annular space isprovided in the fluid passage 12,which space will become enlarged under certain operating conditions, tobe presently described.y Whe`n-the casing is provided with the necessaryquantity of oil vor other fluid, the fluid will fill thecylinder 9-andthe chamber 10, also the fluid passage 12. Under normal conditions Iprefer that the level of the fluid be at least even with the edge ofthewall 11 between Jthe cylinder 9 and chamber 10.

. When the vehicle to which the device is applied, travels over unevenroads, passes over ruts, or strikes an obstruction, the body of thevehicle will lower, due to its beingsup-l ported by the springs 6, whichbecome flexed; the result being that the casing moves downwardly withthe body of the vehicle and positions the actuating lever 27 at an angleto the horizontal. This causes the actuating arm 28 to assume a similarposition, in which position the free end thereof more closely approachesthe cover 18 of the casing, with the result that both pistons 16 and 33are forced upwardly. This upward movement of the pistons creates suctionwithin the lower portion of the cylinder 9, also within the passage 12connecting the chamber 10fwith said cylinder; the result being that therestricted opening in the fluid passage 12 is enlarged, therebypermitting the fluid in the chamber 10 to be drawn in freely throughsaid fluid passage and into the cylinder 9, causing the fluid in thechamber 10 to be lowered, and filling the enlarged unoccupied portion ofthe cylinder 9 by reason of the elevation of the piston 16 therein. Itis of courseapparent that the main spring 20 lifts the' main piston 16during such action and carries with it lthe auxiliary spring 35 and theauxiliary piston 33 within said main piston, substantially the sameco-relation being maintained betweenL the two pistons after suchoperation as existed before the same, or while in normal position.

when sie Chassis and body of the vehicle move upwardly on what isgenerally termed vehicle spring is flexed, therecovery .of the body willreturn said lever to horizontal position, with the result that the freeend of the actuating arm 28 will again assume the posiltion shown inFig. 2, causing the auxiliary piston 33 to be depressed within the mainpis-` ton against the force of the auxiliary spring- 35 and then causingthe main piston 16 to be depressed within `its cylinder. During thedownward movement of the main piston within its cylinder, oil withinsaid cylinder is forced outwardy from the lower portion thereof into thechamber 10 and by reason of the employment of the means in the fluidpassage'12 illustrated in my aforesaid copending application, thepressure will cause thepassage to be restricted; consequently, as-

suring a slow depression ofthe piston within .the cylinder and thuspreventing a quick rebound. -1

Uton and a naturally slow recovery of the.

It is clear therefore that when the main piston rises, the suctioncreated within the cylinder beneath said piston` will cause anenlargement, of the passage connecting the chamber with the cylinder 9,allowing er portion of the cylinder; whereas, when the piston lowers,said passage becomes restricted and a slow escape of the fluid from thecylinder occurs, This results iny a slow upward recovering movement ofthe body of the pissprings v and 35 to normal positions, thereby,

preventing upthrow of the vehicle body and assuring comfortable ridingfor the occupants.

The essential feature of my invention, howaver, resides in providinginitial shock-absorbing means in conjunction with fluid-resistitng orhydraulic shock-absorbing means ,and adapted to absorb slight jars, suchas created in passing `over Cobblestone pavement or like surfaces, andtherefore where the shocks are slight and occur in quick succession, theforce will not be suiiicient to depress the-main piston but will 'beimparted to and absorbed by the auxiliary spring underneath theauxiliary piston 33, which latter piston moves independent of andvithinthe lmain piston against the power of said 'auxiliary spring, saidspring becoming compressed andreeovc ering itself v'under successivejars and shocks so that easyriding is assured under such conditions, incontradistinction'4 to the ordinary shock absorbers in which theresistance to be overcome by the slight jars or shocks is so greatthatdownward movement of the piston cannot take place until aconsiderable downward flexure of the vehicle body occurs;therefore,'when traveling over Cobblestone pavements or roads havingsimilar surfaces, a resistance is offered which is of sufficient forceto prevent proper flexurelof the springs supporting the vehicle body,the result being that occupants of the vehicle are caused to besubjected to slight jolts, similar to those received when riding on aheavy vehicle not equipped with springs, which jolts are imparted to thespine of the occupant, to his discomfort.

By the use ofmy Lsecondary or auxiliary shock-absorbing device, theseslight shocks or j jars are fully absorbed without placing the mainshock-absorbing device into action.

, Another advantage is that when the force j of the shocks o'r jars aresufficient to fully depress the auxiliary piston, suchforce will besufficient to start the main piston on its downward movement without abreak in the downward movement of the free end of the actuating arm 28so that the gradually increasing force applied to the shock absorberwill be absorbed between the auxiliary shock-absorbing device consistingpf the auxiliary piston 33 and auxiliary spring 35 and the main shockabsorbing device, which includes the cylinder 9, chamber 10, fluidpassage 12 with its regulating mechanisms, main piston 16, and mainspring 20.

I am aware that spring-resisting shock-absorbing means rin which springsof different the fluid to be drawn in quickly to fill the low resistingpowers are employed are not new,

but l believe' that a hydraulic shock absorber v having a mainfluid-resisting absorbing device and an auxiliary spring-resistingabsorbing device for initial shocks, embodied in a unitary structure, orotherwise expressed, within a single casing, has not heretofore'beenused; and therefore r Having thus described my invention, what I claimis 1. A hydraulic shock absorber comprising a fluid-resisting"shriek-absorbing device and a spring-resisting shock-absorbing devicecoaxial with said fluid-resisting shock-absorbing i device, a singlecasing enclosing both shockabsorbing devices, said spring-resistingshockabsorbing devices being brought into action before saidfluid-resisting shock-absorbing device and both shock-absorbing devicesserving the fluid. to flow from each chamber to the other through saidpassage including an initial shock absorbing device whose resistanceforce is fully overcome before fluid will be caused to How from onechamber to the other.

3. A shock absorber comprising a casing lhaving two fluid-containingchambers connected by a passage, controlling means within said passagefor .cont-rolling the flow of fluid fromeach chamber to the'other, meansfor causing the Huid to flow from each chamber lto the other throughsaid passage, and an initial shock absorbing device within said casingadapted to absorb slight shocks and jars without placing saidlast-mentioned means -into action.

4. A shock absorber comprising a casingv said second-mentioned piston,and an actuating arm bearing against the upper end of said'second-mentioned piston.

5. A shock absorber comprising a casing having two chambersand fluidregulating between said'chambers, a main shoclrabsorbing device withinone of said chambers, and an auxiliary shock absorbing device withinsaid last-mentioned chamber adapted to absorb slight shocks -and jarsbefore Lsaidmain shock absorbing device is brought into resist` nu@raction.

I. A shock absorber comprising a casing yhaving two chambers and fluidregulating means between said chambers, an actuating element, a pistonwithin one of said chambers adapted to draw Huid from the other chamberand also to force fluid thereinto, and a spring shock absorbing devicecarried by said piston with which said actuating element `co-acts, saidpiston being actuated through vthe mediumy of said spring shockabsorbing device when the resisting force of the lat-ter is overcome.

8. A hydraulic shock absorber comprising f a casing, a fluid-resistingshock-absorbing device within said casing, an actuating'lever withoutsaid casing,an initial spring-resisting shock-absorbing device alsowithin said casing interposed between said Vactuating lever andsaid'uid-resisting shock-absorb-- ing deviceand adapted to be broughtinto action before said fluid-resisting sliock-absorbing device. i

9. A shock absorber comprising a casing, spring-resisting 'meanswithinsaid casing to absorb slight shocks, and fluid-resisting meansalso .i within said casingn to absorb Said heavier shocks, lsaidfluidaresisting means being brought into action through the medium ofsaid spring-resisting means when the absorbing force of the llatter isexpended.

10. A shock absorber comprising a casing having two chambers,Huid-regulating means between said chambers, a piston within one ofsaid' chambers `having'an axial bore e11- larged at its upper end 'toform an upwardlyfacing shoulder, .a piston within the enlarged 4 upperend of'said axialbore, means to retain -said piston within the enlargedupper end of said bore, and a spring within said bore exerting forceupwardly against said last-mentioned piston. l

11. A shock absorber comprising a casing having two chambers,fluid-regulating means between said chambers, a piston within one ofsaid chambers having its'upper end reduced in diameter and having anaxial bore opening at the' top -of said piston and enlarged at its upperend, a disk within said enlarged upper end, a stop device applied to thereduced upper end of said piston against which said disk normally bears,and a spring within said .axial bore `bearing against the under side ofsaid disk.

12. A shock-absorber comprising a casing having two chambers,fluid-regulating means between said chambers, a piston within one ofysaid chambers having a reduced upper end forming a neck and having anannular groove in said neck, said piston having an axial bore, a stopring applied to said neck and fitted into the annular groove thereof,said stop ring overhanging the'wall of said axial bore, aA piston withinsaid axial bore bearing against the overhanging portion of said stopring, and a spring `in said axial bore bearing against the under side ofsaid last-mentioned piston. l

13. In a shock absorber, a casing having l,two chambers,`fluid-regulating means between said chambers and two spring-retainedpistons within one of said chambers, one -of ysaid pistons being broughtinto action before the other 4to absorb-slight shocks and said otherbeing brought into action `toabsorb heavier shocks.

14. A shock absorber comprising a casing having ltwo chambers separatedby a wall, fluid-regulating Vmeans between said chambers, aspring-pressed piston within one ofv said chambers having an axial boreenlarged at its outer end, a stop device overhanging the wall of theenlarged upper end of said axial bore, a disk within the enlarged upperend of said axial bore having an opening therein, a'spring in said axialbore to nor mally force said disk againstsaid stop device, and anactuating element within said casing adapted to be` connected witha partof a vehicle agd adapted to bear against lsaid disk.

'ADOLPH W. r. MANZEL.

